Spectroscopic analysis devices include those which allow light from the spectroscope to be received using a plurality of light receiving elements, such as a photodiode array. In spectroscopic analysis devices of this sort, the lights of each wavelength separated by the spectroscope are received by light receiving elements corresponding to each wavelength, making it possible to measure the quantity of light of each wavelength.
The light received by each light receiving element in a spectroscopic analysis device of the sort described above is not necessarily limited to light which has passed through a sample and was then separated by the spectroscope. For example, if light which has not entered the spectroscope or light which has been reflected by various optical components in the spectroscopic analysis device (so-called stray light) enters a light receiving element, a greater quantity of light will be received by the light receiving element than the quantity of light which has passed through the sample.
The effect of such stray light on analysis is especially marked in the wavelength region where the absorbance in the sample is high, i.e. the wavelength region where the quantity of light received by the light receiving element is small. Furthermore, in a configuration where light of different wavelengths is received with a plurality of light receiving elements, there is the concern that the effect of stray light may be influenced by the position of each light receiving element and the like.
To eliminate the above-described effect of stray light on analysis, the quantity of stray light is commonly measured (for example, see undermentioned Patent literature 1). This Patent literature 1 discloses measuring the quantity of stray light in the short wavelength region where absorbance in the sample is high (where transmittance is low) (Paragraph (0004), etc.).